According to the New York Post, the jerseys, which are “proudly made in the USA,” rolled out on Sept. 7, the same week Nike announced Colin Kaepernick, the first NFL player to kneel during the national anthem as a protest against racism, as one of the faces for advertisements commemorating the 30th anniversary of its “Just Do It” slogan.

A campaign spokesperson told the Post that sales have been “brisk.”

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“Our theme originated out of President Trump’s love for the American flag and his fervent belief that Americans should always stand for our National Anthem,” Lara Trump, the president’s daughter-in-law said.

Kaepernick was a quarterback with the San Francisco 49ers for six years. He stirred a national controversy by taking a knee while the anthem was played before games during the National Football League’s 2016 season to draw attention to police killings of black men and other issues.

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The anthem protests, soon embraced by other players, raised the ire of some NFL fans and Trump, who has said he would love to see NFL owners fire football players who disrespect the American flag.

Kaepernick has a jersey of his own, which is currently sold out, according to the former quarterback’s website. The jersey features an embroidered #ImWithKap hashtag on the front along with the number seven, and #IknowMyRights tag stitched on the bottom. All profits from the jersey sales goes to his “Know Your Rights” youth camp.